Punch presses are typically configured to hold a plurality of tools for forming a variety of shapes and sizes of indentations and/or holes in sheet workpieces, for example, sheet metal. Tools of this sort commonly include at least one punch assembly and corresponding die. In a multiple station turret punch press, a rotatable turret includes a plurality of bores, which hold a corresponding plurality of punch assemblies above a workpiece support surface, and a corresponding plurality of die receiving frames are located below the workpiece support surface.
A conventional punch assembly includes a punch guide, a punch body and a punch tip, which may be either fixedly or releasably attached to the body. The punch body and tip are slidably engaged within the punch guide for reciprocal, axial movement along a central longitudinal axis of the punch guide. When such a punch assembly, and a corresponding die, are mounted in a press and located in a working position of the press, beneath the ram (or integrally connected to the ram), the punch tip is driven out from the punch guide, through an opening in a stripper plate, in order to form an indentation or a hole through a sheet workpiece. The stripper plate, which is attached to an end of the punch guide, prevents the workpiece from following the punch tip, upon retraction back into the punch guide.
Those skilled in the art appreciate that punch assemblies require regular maintenance and modification, for example, to sharpen worn punch tips, to replace worn punch tips, to replace punch tips of one shape, or footprint, with those of an alternate shape, and/or to adjust a position of the punch body, and corresponding punch tip, within the assembly to account for different lengths thereof. Although a variety of punch assembly configurations, which facilitate these types of modifications, have been disclosed, there is still a need for new punch assembly configurations and methods that increase the ease and the speed by which these modifications can be made.